All the Ways Your Brain Can be Tricked by Comparisons

Want to see a gender-neutral face turn masculine? How about a neutral face turn friendly, or a sharp picture turn fuzzy? This brief video will take you through all the ways your brain adapts to a stimulus, until you see things that simply aren’t there.

We rely heavily on comparison to make judgments. The pattern is simple. We are shown an image, then asked to adapt to a new image, and then shown the original image again. In the few seconds that we stared at the second image, our brain adapted to it sufficiently to make the original look totally different.

The first few adaptive illusions are pretty well-known: for instance, focusing on a negative of an image will make the image appear, later, when looking at a white screen. But at the forty-nine second mark things start getting weird, when a black and white photo suddenly appears to have colour.

The effect isn’t limited to simple optical illusions like colour and negative images. Our ideas of gender and expression are also based on comparison. We see a succession of faces, from masculine to feminine. By switching between the faces, the film lets us see the same face as masculine, feminine, and somewhere in between. It lets us see a face with a neutral expression as happy, by giving us a taste of what angry looks like.